Gonzalo Vegas Sanchez-Ferrero, PhD Instructor in Radiology Department of Radiology Brigham and Women’s Hospital Harvard Medical School

Abstract

Quantitative analysis of CT images in multicenter studies involves dealing with intrinsic disparities in the density measures due to differences in the acquisition parameters and/or scanners. Clinical studies have observed spatial discrepancies in the attenuation levels for the same densities due to noise characteristics. In this seminar, I will introduce new methods to characterize the spatial differences across acquisition protocols and scanners from the emitted photon to the reconstructed voxel. These methods make it possible to understand the origins of imaging confounders and define a harmonization methodology that reduces or even eliminates their effect. The talk will cover the statistical characterization of polychromatic X-ray spectra, the characterization of spatially variant noise, bias, and resolution in reconstructed CT scans, and the definition of harmonization methods to remove confounders.

Short Bio

Dr. Vegas is an Instructor in Radiology at the Brigham and Women’s Hospital. Originally trained in signal theory and mathematics, Dr. Vegas joined in 2015 the Applied Chest Imaging Laboratory run by Dr. San José Estépar and Dr. George R. Washko to develop CT harmonization methodologies scans for multicenter studies. His research interests include noise characterization, signal estimation, and quantitative imaging. Dr. Vegas has coauthored over 100 publications, one reference book on MRI noise characterization, and was awarded a Marie Curie grant from the European Commission. He is currently developing his scientific program on CT harmonization to assess parenchymal injury progression under an NIH K25 career development award.